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Li, C.

Publications and source records attributed to Li, C..

At least 109 records · Page 6Linked to original sources

PlantP450Dock: an Automated Molecular Docking Pipeline of Plant Cytochrome P450s

Cytochrome P450 enzymes (CYPs) are the primary drivers of chemical diversification in plant secondary metabolism; however, fewer than 10% of the superfamily members have been functionally characterized. Computational docking provides a scalable strategy to prioritize candidates for experimental validation, yet prevailing workflows are poorly adapted to plant P450s because AlphaFold-predicted structures lack the essential heme cofactor and conventional flexible-residue selection relies on subjective geometric cutoffs. To address these limitations, we developed an automated pipeline--PlantP450Dock--that unifies heme cofactor implantation, molecular dynamics-based conformational sampling, data-driven flexible residue selection, and semi-flexible docking within a single integrated workflow. The heme is transferred from a crystallographic template to the AlphaFold model via a local coordinate transformation algorithm, achieving a positional deviation of less than 0.2 [A] relative to the experimentally determined CYP73A33 structure (PDB: 6VBY). Subsequent 100 ns molecular dynamics simulations confirmed faithful preservation of the Fe-S coordination geometry (2.61 {+/-} 0.08 [A]) across all trajectory frames. A singular value decomposition-based heme-plane filtering strategy objectively identified distal active-site residues for flexible treatment, eliminating user-dependent subjectivity. Cross-family validation against four phylogenetically distinct P450s (CYP73, CYP711, CYP706, and CYP701) generated catalytically competent binding poses with substrate-to-heme-iron distances of 2.8-4.4 [A] without enzyme-specific parameterization. Released as an open-source tool, this pipeline furnishes the plant science community with a standardized, reproducible computational framework to accelerate functional annotation of the largely unexplored plant P450 families.

bioinformatics↗

Near-Infrared-II Chemo-Optogenetics for Deep-Brain Stimulation

Precise activation of ion channels enables fine-tuned control of neuronal excitability, providing a powerful strategy for dissecting and modulating neural circuits. Although optogenetics offers high spatiotemporal neuronal manipulation with cell-type specificity, its reliance on visible light (400-650 nm) limits tissue penetration to millimeter depths, restricting applications in deep-brain stimulation. Here we report a near-infrared-II (NIR-II)-sensitive calcium channel, HaloNeu, created by genetically fusing a circularly permuted HaloTag (cpHaloTag) to the thermo-sensitive transient receptor potential vanilloid 1 (TRPV1) and covalently conjugating NIR-II photothermal nanotransducers (HPN). The HaloNeu enables non-invasive neuromodulation at depths up to 1.0 cm at ultralow laser power ([~]60 mW/cm2) and up to 5.0 cm under the safe exposure limit ([~]1 W/cm2) with 1064 nm laser illumination. Remarkably, HaloNeu maintains stable, on-demand neuron-specific modulation for over two months in vivo, providing sustained activation of ventral tegmental area (VTA) circuits and effective alleviation of Parkinsonian symptoms in mouse models. These results establish HaloNeu as a robust and versatile platform for cell-type-specific, deep-tissue, and chronic neuromodulation, with broad implications for neuroscience and neurotherapeutics.

neuroscience↗

Temporal-deviation-driven community detection uncovers early-warning signals for critical transitions in complex diseases

Early detection of critical transitions in complex diseases is crucial for timely clinical intervention. However, as patients often provide only a single snapshot, identifying sample-specific early-warning signals (EWS) from a dynamical evolution perspective remains challenging, coupled with high-dimensional noise amplification. Here, we present TD-COM, a framework for detecting personalized EWS of critical transitions via single-sample community detection. By constructing a temporal perturbation map STDN, TD-COM captures latent dynamical perturbations inferred from static individual profiles. Synergizing these temporaldeviation signals with static topological features, TD-COM implements a multilevel node filtering strategy during community detection, effectively suppressing single-sample noise. Validated on hour-scale, multi-year, and multi-decade transcriptomic data, TD-COM robustly detects critical states preceding clinical deterioration and uncovers their underlying molecular mechanisms. Comparative experiments demonstrate that TD-COM outperforms existing methods in accuracy and topological robustness. Thus, TD-COM provides a generalizable framework for personalized early warning of complex diseases, particularly when longitudinal sampling is infeasible.

bioinformatics↗

Alternative organelle targeting of OPA1 mediates fatty acid release from lipid droplets

Mitochondria and lipid droplets (LDs) are functionally coupled to coordinate fatty acid utilization and storage. However, a comprehensive understanding of mitochondria-LD alliances remains elusive. We have identified a previously unrecognized role for optical atrophy 1 (OPA1), a mitochondrial fusion factor, in the regulation of fatty acid release from LDs. We demonstrated that OPA1s exon 4 adapts an amphipathic helix to target OPA1 to LDs. OPA1 localized to LDs promote fatty acid release by facilitating the recruitment of lipases to LDs. In addition, OPA1s residence on LDs competes with its mitochondrial entry, influencing mitochondria fusion and connectivity. Furthermore, the S158N polymorphism within OPA1s exon 4 exhibiting attenuated fatty acid release from LDs is associated with changes in metabolic traits in pediatric cancer survivors. Altogether, our findings reveal that OPA1 actively mediates fatty acid release from LDs and provide a mechanistic link between OPA1 and human metabolism.

cell biology↗

From Face to Person: Disentangling the Neural Origins of the N170, N250, and SFE in Familiar Face Recognition

Recognizing familiar faces is essential in our everyday life. ERP studies have identified three components sensitive to face familiarity (N170, N250, and SFE), but whether these signals arise from visual experience, identity information, or semantic knowledge remains to be directly tested. Using a sequential familiarization paradigm, we progressively trained the same initially unfamiliar faces with visual exposure, identity associations, and biographical knowledge, recording EEG after each phase. The N250 emerged immediately after visual familiarization and remained stable thereafter; the N170 appeared only after identity familiarization; and the SFE exhibited a graded, enhanced pattern: absent after visual exposure, emerging after identity training, and reaching maximum effect after semantic familiarization. These findings provide the first direct evidence that these three ERP markers are differentially driven by distinct types of information, revealing the temporal dynamics through which person-related knowledge transforms a face percept into the recognition of a known person.

neuroscience↗

Integrative taxonomy of Trichiurus (Scombriformes: Trichiuridae) reveals a new cutlassfish species from Java, Indonesia

The genus Trichiurus is the most economically valuable fish in the family Trichiuridae, currently recognized to include 10 valid species. However, historically numerous morphologically similar congeners have been erroneously assigned as synonyms or subspecies of T. lepturus. In this study, we examined 16 hairtail specimens collected from the southern waters of Java Island, Indonesia. Integrated morphological and mitochondrial phylogenetic analyses (COX1 and 16S rRNA), compared against global Trichiurus sequences, revealed that these specimens form an independent lineage that diverged early from other congeners. Consequently, we describe this lineage as a previously undescribed cryptic species. Diagnostic characters include: first anal-fin spine below 36th-37th dorsal-fin rays; anus below 35th-36th dorsal-fin rays; anteriormost tip of supraoccipital well posterior to posterior distal margin of eye; anterior margin of the pectoral-fin spine non-serrated; fangs on both jaws with barb-like processes; upper jaw long, mean 16.6% (15.5-17.6%) of preanal length; snout short, 12.0% (10.9-13.1%) of preanal length; eye small, diameter 5.3% (4.3-5.7%) of preanal length; and absence of hyperostosis on dorsal cranium. We herein propose the name Trichiurus javaensis sp. nov., and provide a formal morphological description and diagnostic characterization of this species.

zoology↗

The abscopal effect of Combination IRE with anti-PD-1 achieves local ablation and systemic control of PDAC

Irreversible electroporation (IRE) has shown promise for treating pancreatic ductal adenocarcinoma (PDAC), but whether IRE can induce an abscopal effect is not established. We demonstrated that the combination of IRE and anti-PD-1 antibody could trigger robust abscopal effects in preclinical models of metastatic PDAC. Data from multiple in vivo models, RNA-seq, scRNA-seq, and spatial immunofluorescence provide compelling evidence that IRE induced mitochondrial dysfunction and cellular stress, which triggered activation of the cGAS-STING pathway and subsequent systemic antitumor effects. IRE also led to inflammatory response characterized by tumor infiltration of myeloid cells and their polarization toward M1 state, turning immunologically "cold" tumors into "hot" tumors. Moreover, the presence of T cell/B cell clusters in tumors from mice treated with IRE plus PD-1 and the lack of antitumor efficacy in B cell knockout mice bearing orthotopic murine PDAC tumors indicate that B cells play an important role in IRE-mediated systemic antitumor immunity. SignificanceThis study shows that IRE plus a checkpoint inhibitor represents a promising therapeutic strategy for PDAC and supports advancing this treatment toward clinical translation. Our data also support potential combination strategies with immunomodulatory agents that can recruit and reprogram B cells to support T cell activation and cytotoxic effector functions.

immunology↗

Rapid, Non-Destructive Visualization of α-Zein Expression and Grain Protein Concentration in Maize Using the Floury2-RFP Reporter Transgene

Kernel composition traits in maize, including protein accumulation, are of broad interest. The amount of the most abundant proteins in maize endosperm, the -zeins, can vary dramatically among genotypes and in response to soil nitrogen supply. Targeted reductions in -zein accumulation can improve nitrogen utilization and the nutritional quality of maize grain but have traditionally required expensive and destructive phenotyping methods. The Floury2-RFP (Fl2-RFP) reporter gene enables rapid, non-destructive visualization of -zein accumulation in individual maize kernels under white light. This feature is due to the high expression level programmed by the Fl2 promoter, the stability of zein proteins, and the use of monomeric RFP, which emits fluorescence without the need for multimerization. This study aimed to develop a method to quickly document and quantify Fl2-RFP accumulation using camera or smartphone images of either ears or shelled kernels. Results show images of shelled kernels processed with FIJI software capture the Fl2-RFP reporter phenotype better than images of ears. Fl2-RFP confirms the strong maternal control of -zein accumulation and, like grain protein concentration, responds to soil nitrogen supply. The Fl2-RFP phenotyping pipeline effectively quantified Fl2-RFP accumulation by color features from both camera and smartphone images. Smartphone imaging of Fl2-RFP in a diverse population of inbreds followed by elastic net regression of extracted image features predicted kernel protein concentration, as measured by near-infrared spectroscopy, with moderate accuracy (R2 = 0.68, MAE = 0.76, RMSE = 0.93). The spectral features that were most predictive of kernel protein concentration varied depending on whether the background endosperm color was white or yellow. The integrated analysis of Fl2-RFP intensity and grain protein concentration indicates genetic variation for kernel protein accumulation and N-responsiveness that is distinct from the well-studied -zeins. Our findings highlight the Fl2-RFP reporter gene as a valuable tool for investigating the genetic complexity of grain protein concentration and associated traits in maize.

plant biology↗

The Par complex regulates apical-basal cell polarity through modulation of FAK signaling homeostasis

Cell polarity complexes are essential for embryogenesis, but their regulatory mechanisms during early developmental transitions remain incompletely understood. Here, we individually deleted the Crumbs, Par, and Scrib polarity complexes in mouse embryonic stem cells (mESCs). While loss of any single complex did not affect pluripotency or proliferation, deletion of Par complex disrupted the naive-to-primed transition and impaired subsequent differentiation, particularly lumen formation in neural tube organoids. Mechanistically, Par complex deficiency led to hyperphosphorylation of focal adhesion kinase (FAK) at the primed stage, driving a morphological shift from flat monolayer clusters to dome-shaped colonies. FAK inhibition rescued the aberrant morphology. Upstream, Par complex loss increased AKT phosphorylation, which remodeled extracellular matrix (ECM) and regulated integrin signaling via FURIN-LEFTY, ultimately modulating FAK activity. In addition, conditioned medium from wild-type cells partially rescued differentiation defects in Par knockout cells in a LEFTY-dependent manner. These phenotypes were consistently observed in naive-to-primed transition, neural stem cell differentiation, embryoid body formation, teratoma assays, and neural tube organoid differentiation. Together, these findings establish a Par complex-AKT-FURIN-LEFTY-ECM-integrin-FAK signaling cascade that links apical-basal polarity to early lineage specification and morphogenesis, providing a mechanistic framework for how polarity cues are translated into developmental outcomes. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/722465v1_ufig1.gif" ALT="Figure 1"> View larger version (64K): org.highwire.dtl.DTLVardef@179e0adorg.highwire.dtl.DTLVardef@8d83bdorg.highwire.dtl.DTLVardef@c425fforg.highwire.dtl.DTLVardef@19a8ee5_HPS_FORMAT_FIGEXP M_FIG C_FIG Significance StatementThis study elucidates the molecular mechanism by which the Par complex regulates the establishment of cell polarity. The authors demonstrate that the Par complex promotes the expression of the protein convertase FURIN via AKT signaling, thereby enhancing the maturation and secretion of LEFTY protein. This process remodels the ECM and modulates integrin signaling, ultimately regulating FAK activity and controlling the establishment of cell polarity. These findings reveal how polarity cues govern early lineage specification and morphogenesis, with implications across multiple developmental contexts.

developmental biology↗

SARS-CoV-2 (E)-protein induces rapid TLR2-mediated T cell activation in mouse lungs revealed by intravital lung microscopy

Mounting evidence indicates that T cells can operate in an innate-like mode challenging the classical description of T cells as strictly adaptive immune effectors. T cells can engage innate pattern recognition receptors to mount rapid but antigen-nonspecific responses to infection or cellular stress. This study observed that CD8+ T cells, and to a lesser extent also CD4+ T cells, responded to viral proteins in the mouse lung quickly in an innate-like fashion. We employed intravital lung microscopy to visualize infiltration of CD8+ T cells into the lung following intratracheal instillation of the SARS-CoV-2 envelope (E)-protein. Here, we demonstrate acute recruitment of CD8+ from the pulmonary microcirculation into the lung as early as 4 and 24 hours after (E)-protein instillation. The acute infiltration of CD8+ T cells was not observed in Tlr2-/- mice. Immunohistochemistry analysis of mouse lungs revealed T cell accumulation in nodular inflammatory foci (NIF) of the lung at perivascular regions and around large airways. Stimulating spleen-derived CD8+ T cells from wild-type mice with (E)-protein ex vivo in combination with cytokines or TCR agonists significantly upregulated CD69 and activated secretion of interferon (IFN){gamma} which was not observed with CD8+ T cells isolated from Tlr2-/- mice. These findings indicate rapid bystander activation of CD8+ T cells by the SARS-CoV-2 envelope (E)-protein that depends on (E)-protein sensing by TLR2. This innate-like CD8+ T cell response to SARS-CoV-2 (E)-protein may offer novel opportunities for diagnostic and therapeutic development, warranting further investigation.

immunology↗

An Essential Role of the AMPK-Related Kinase SNRK in Regulating Drosophila Sleep

Protein kinases are important regulators of sleep in animals, but their loss-of-function mutations usually show moderate phenotypes. We report here that sucrose non-fermenting related kinase (SNRK), a member of the AMP-activated protein kinase-related kinase (ARK) family, plays an essential role in sleep regulation: Snrk gene knockout resulted in a profound loss of night-time sleep phenotype, much stronger than that of the well-known ARK member Sik3. This phenotype was completely rescued by neuronal SNRK expression. SNRK in adulthood was required for sleep. Catalytic and regulatory sites in SNRK were important for sleep. A chemoconnectomic (CCT) screen revealed SNRK functioning in cholinergic neurons whose activation is known to inhibit sleep. Sleep loss in SNRK mutants was rescued by pharmacological blockade of nicotinic acetylcholine receptors. Our findings have uncovered a fundamental role for SNRK in cholinergic neurons to regulate sleep.

neuroscience↗

The discovery of missing taxane C13α-O-deacetylases re-delineates the biosynthetic pathway of paclitaxel

The prevalence of naturally occurring C13-acetoxy taxanes, together with the presence of a native C13-acetyltransferase in yew trees, suggests that the natural biosynthetic pathway for paclitaxel may involve a cryptic C13-O-deacetylation step. However, whether a putative taxane C13-O-deacetylase (T13dA) acts in the pathway of paclitaxel biosynthesis remains elusive. Herein, we functionally characterized two novel taxane C13-O-deacetylases (T13dA1 and T13dA2) from Taxus x media cell cultures, providing experimental evidence for the molecular and biochemical plausibility of C13-O-deacetylation in paclitaxel biosynthesis in Taxus species. Furthermore, T7dA1, a novel taxane C7{beta}-O-deacetylase with higher activity than the reported T7dA was discovered and characterized here. Notably, we reconstituted a new 19-gene pathway enabled by the integration of a C13-O-acetylation-deacetylation module for the de novo biosynthesis of baccatin III in Nicotiana benthamiana leaves, reaching a yield of 71{square} g{square} g-1 DW, much higher than that obtained from the 17{square} gene pathway lacking this module. These findings not only demonstrate the functional importance of the C13-O-acetylation-deacetylation module as a branch within the paclitaxel biosynthetic network, but also expand the multi-branched taxane metabolic network in Taxus and provide novel enzymatic tools and engineering strategies to facilitate heterologous pathway reconstitution and efficient paclitaxel production.

biochemistry↗

Mapping fibrotic microenvironments: single-cell and spatial profiling of Schistosoma mansoni-induced tissue fibrosis

Schistosoma-induced tissue fibrosis, driven by immune response to trapped schistosome eggs, is the principal cause of pathology and schistosomiasis-related morbidity. While praziquantel effectively clears adult parasites, no therapies exist to target eggs or egg-induced tissue fibrosis. Here, we utilise single-cell spatial transcriptomics to define the high-resolution molecular architecture of the fibrotic niche in Schistosoma mansoni-infected mice at 8 weeks post-infection. Our data reveal that the host executes divergent, organ-specific biological programs: constructing a rigid, concentric fibrotic granuloma for permanent egg sequestration in the liver while building a flexible, discontinuous collagen architecture in the intestine to facilitate egg transit. Spatially resolved cell-cell interaction analysis, unprecedented in schistosome-induced fibrosis, identifies the strongest cellular interactions between macrophages and collagen-producing cells, with TGF-{beta}-dominant ligand-receptor pairs in the hepatic niche and integrin-centered pairs in the intestine. Despite this architectural divergence, we detected a core signature of five ligand-receptor pairs shared across both tissues, suggesting shared signalling interactions that could be leveraged for pan-tissue therapeutics for treating schistosome-induced fibrosis. Together, these findings provide the first high-resolution spatial atlas of schistosomiasis-associated fibrosis and provide a foundational framework for discovering novel drug targets capable of reversing established tissue damage, addressing a critical clinical gap where current therapies fail.

molecular biology↗

Explainable Prototype Booster: Enhancing Latent Representations of Foundation Models for Gene Expression Prediction

Spatial transcriptomics (ST) is a cutting-edge technology that measures gene expression while preserving spatial context and generating pathology-grade tissue images. Although ST has enabled numerous discoveries and demonstrated a huge application potential in pathological diagnosis and prognosis, the technology remains time-consuming and costly. The ability to predict gene markers of cancer from histological H&E-stained tissue images can overcome these technological barriers to open new horizons for precision and personalised pathology. Recently, foundation models have demonstrated improvements in generating general-purpose embeddings of H&E-images. However, these improved representations are not optimized for gene expression prediction and lack task-specific adaptability. To address this limitation, we propose the Explainable Prototype Booster (EP-Booster), which incorporates biological prior knowledge to guide the construction and training of learnable prototypes for embedding refinement, thereby improving gene expression prediction. Importantly, model predictions are inherently interpretable through pathway-level attributions associated with the prototypes. Extensive experiments across multiple datasets, cancer types, and spatial transcriptomics platforms demonstrate that EP-Booster consistently outperforms existing methods. Moreover, EP-Booster can be integrated with diverse foundation models to enhance task-specific representations, thereby improving predictive performance and biological interpretability in clinically relevant applications, including cancer biomarker prediction, survival analysis, and drug response prediction.

bioinformatics↗

Structural Activation of DNA Unwinding by MCM8/9/HROB

The minichromosomal maintenance MCM8 and MCM9 proteins form a heterohexameric complex that acts to unwind or remodel duplex DNA in DNA recombination and repair pathways. Mutations or absence of MCM8/9 have been linked to infertility, sex-specific deficiencies, and several cancers. Recently, HROB has been identified as a critical cofactor of MCM8/9; however, the mechanism underlying activation of MCM8/9 DNA binding and unwinding remain unclear. Here, we present dynamic structures of MCM8/9 with DNA, HROB and ATP analogs using cryo-electron microscopy. DNA binding induces a pronounced rotational rearrangement between the N-terminal DNA binding and C-terminal AAA+ ATPase domains, reorganizing DNA-binding loops into a staircase configuration that supports DNA engagement. Remarkably, HROB associates with both halves of the heterohexamer and drives a similar rotation prior DNA binding for localizing MCM8/9 to sites of crosslink damage and unwinding, culminating in a unified mechanistic model for MCM8/9 helicase function and its activation by HROB.

biochemistry↗

Analysis of persistence thresholds for a nonlocal PDE--ODE model of bacterial persister cells

Within many bacterial colonies, persister cells exist as a subpopulation that is tolerant to antibiotics and other stressors, yet not genetically distinct from the rest of the colony. A recent study has proposed epigenetic inheritance as a mechanism that leads to the presence of persister cells. We analyze a nonlocal PDE-ODE model introduced in that study to describe the epigenetic inheritance process and establish its mathematical well-posedness, including existence, uniqueness, and nonnegativity of solutions. We identify a sharp parameter threshold delineating extinction from persistence of the colony: below this threshold the washout equilibrium is globally asymptotically stable, while above it a unique positive equilibrium exists and the population is weakly persistent. Notably, this threshold is independent of the internal community structure.

microbiology↗

Pan-cancer circular genomics identifies intratumoral Staphylococcus lugdunensis as a metabolic driver in bladder cancer

Intratumoral microbiota play key roles in cancer but are challenging to profile due to low biomass. We developed CIRCMIP, an enzymatic pipeline that eliminates linear DNA to enrich bacterial genomes, achieving 100-fold higher sensitivity than standard metagenomics. Applied to 312 pan-cancer specimens, CIRCMIP identified Staphylococcus lugdunensis as a signature bacterium enriched in early-stage bladder cancer (BLCA), where its presence predicts poor survival. Integrated modeling and lipidomics revealed that Staphylococcus lugdunensis colonization drives aberrant lipid metabolism with secretion of LPC14:0. Both Staphylococcus lugdunensis and LPC14:0 drive BLCA progression by promoting fatty acid uptake and {beta}-oxidation. Mechanistically, chemical proteomics revealed LPC14:0 as a direct PPAR{delta} ligand, binding via hydrogen bonds with Thr292/Thr289. This activation upregulates fatty acid transporters (CD36, FABP4) and metabolic enzymes (ACOX2), fueling malignant proliferation. Furthermore, CIRCMIP-derived biomarkers show robust diagnostic accuracy, establishing a new research paradigm and revealing the Staphylococcus lugdunensis-LPC14:0-PPAR{delta} axis as a therapeutic target in bladder cancer. HIGHLIGHTO_LICIRCMIP leverages DNA circularity to achieve 100-fold sensitivity in pan-cancer bacteriome profiling. C_LIO_LIStaphylococcus lugdunensis is a bacterial signature in early-stage bladder cancer that predicts poor patient survival. C_LIO_LIBacteria-derived LPC14:0 acts as a direct ligand for PPAR{delta} to drive host malignant metabolic reprogramming. C_LIO_LITargeting the Staphylococcus lugdunensis-LPC14:0-PPAR{delta} axis abrogates malignant progression in bladder cancer. C_LI

cancer biology↗

A Brain-wide Neuronal Spiking and Behavior Dataset for Working Memory-Specific Activation and Reactivation in Mice

AbstractHow do millisecond-scale neural activities mediate multi-second behaviors such as working memory? This dataset provides brain-wide, high-spatiotemporal-resolution single-unit spiking activity recorded from 40 head-fixed mice performing an olfactory delayed paired-association (ODPA) task, encompassing 33,028 neurons across 62 anatomically defined brain regions. Utilizing this dataset enables the extraction of millisecond-scale within- and cross-region spike couplings enriched among memory-content-selective neurons. These couplings may be used to identify higher-order, hierarchically structured activity motifs. Because these multi-neuron patterns are captured both during active task performance and spontaneous inter-trial intervals, this dataset provides a resource for studying replay-related activity and for testing hypotheses about circuit-level processes associated with perceptual working memory. The dataset supports broad investigations into cross-regional spike organization, functional coupling, and temporal coding in working memory circuits.

neuroscience↗